IRES, Chapter 2 Scope of energy statistics Draft 1
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Chapter 2 Scope of energy statistics
This draft represents an attempt to put together various ideas/suggestions relevant to the
description of the scope of energy statistics. It contains a lot of questions which the Group
has to
discuss and to provide guidance on for prior to further drafting. Please, comment on the
general
structure and the suggested concepts and definitions. Please, indicate topics which, in your
view,
should be added or dropped.
A. Energy and energy statistics
2.1. Energy and its forms. Energy, as generally understood in physics, is as a measure of the
capacity of a physical system to do work. [is there a definition accepted by the scientific
community? Do we need to cite it?]. Energy exists in different forms - such as light, heat,
and
motion - but they can all be put into two categories: potential (for example, the energy stored
in
matter) and kinetic (the energy of motion). Examples of potential energy are chemical energy
(energy stored in the bonds of atoms and molecules) and nuclear energy (energy stored in the
nucleus of an atom). Potential energy is often referred to as “stored” energy. Examples of
kinetic
energy are electricity and thermal energy.
2.2. All physical processes involving transformation/conversion of energy forms are
governed
by fundamental principles of the laws of thermodynamics, which are briefly described in Box
2.1.
In very simplified terms, the first law of thermodynamics implies that energy can neither be
created
nor destroyed, it can only be converted from one form to another; in other words, the amount
of
energy in a closed system remains constant. The second law of thermodynamics express the
idea
that with each energy conversion from one form to another, some of the energy becomes
unavailable for further use. These fundamental laws behind energy are reflected in the energy
balances and in the energy accounts.
IRES, Chapter 2 Scope of energy statistics Draft 1
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Box 2.1: Energy in physics and laws of thermodynamics
Source: Based on the paper “Fundamentals: Fuels, Sources, Energy Systems and the Laws of
Thermodynamics” Anderss Johansson prepared for the 3 rd Oslo Group meeting
[How much physics do we need to bring into IRES at this stage? Is the above about to
be
right amount? Obviously, when taking about definitions of particular energy products
we
need to be back to it.]
2.3. Energy in statistical context. The physical concept of energy is used in statistics to define
its specialized field – energy statistics - by: identifying energy products, their energy content
and
activities which produce and transform energy products; defining the boundary of energy
sector;
and describing the concept of energy balance [..] etc. [OG is asked to provide input/advice
on
how to develop better the text linking energy as physical concept to energy statistics]
2.4. Energy statistics. Energy statistics, understood broadly, may encompass any data helpful
to
understand: the availability of energy resources; the production, transformation, distribution
and
consumption of energy products; and the size, structure and activities of energy sector. [Do
we
want to provide a general definition of energy statistics?]. IRES presents definitions and
classifications for statistics on stocks and flows of energy products and on their uses in the
compilation of energy balances and accounts and selected additional statistics that are
relevant,
broadly speaking, for energy policies. Countries are encouraged to define the scope of their
national energy statistics taking into account their needs, priorities and resources, by
identifying
those data items relevant for national compilation from the recommended reference list in
Chapter
6 as well as by adding additional items if country intends to define the scope of its energy
statistics
more broadly.
The laws of thermodynamics describe the limits and possibilities for the transport and transformation of heat
and work in thermodynamic processes and systems.
0. If two thermodynamic systems are in thermal equilibrium with a third, they are also in thermal
equilibrium with each other.
The zero law is essentially a consequence of the second and has to do with temperature and
thermal equilibrium.
1. “The increase in the internal energy of a system is equal to the amount of energy added by heating
the system, minus the amount lost as a result of the work done by the system on its surroundings.”
The first law has to do with the conservation of energy and that work and heat are equivalent and
mutually transferable.
2. “Heat cannot spontaneously flow from a material at lower temperature to a material at higher
temperature”
The second law has huge ramifications on the application of the first law, e.g. by stating the only
possible direction of heat transfer (from warmer to colder) and implicitly introducing the idea of
efficiencies. The second law also introduces the concept of entropy. Entropy is popularly
described as an implicit measure of the disorder of a system – a measure of the number of possible
states of the system’s components.
3. “As a system approaches absolute zero, all processes cease and the entropy of the system
approaches a minimum value.”
The third law of thermodynamics is also a consequence of the second law, and it says that as the
temperature approaches absolute zero (_273.15 °C or 0 K) all processes stop.
IRES, Chapter 2 Scope of energy statistics Draft 1
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B. Basic concepts and boundary issues
2.5 Energy resources and energy reserves. Energy resources refer to “all non-renewable
energy
resources of both inorganic and organic origin discovered in the earth’s crust in solid, liquid
and
gaseous form”1. In broad terms, energy reserves are the part of the resources, which based on
technical and economic and other relevant (e.g. environmental) considerations could be
recovered
and for which extraction to some extent is justified. The exact definition of reserves depends
on the
kind of resources in focus. Even though information on energy resources and reserves is
generally
not considered as part of energy statistics, countries collect this information to monitor the
depletion of energy resources. [Does OG agree that the collection and dissemination of
data on
energy resources and reserves is not in scope of basic energy statistics?]
2.6 Energy and non-energy products. The term “energy products” refers to products that are
used or may be used as sources or carriers of energy such as combustible fuels as well as to
any
form of usable energy such as heat and electricity. [We need to discuss and agree on a
definition
of energy products and boundary between energy and non-energy products. Some
examples
might be also helpful.] Energy products include both primary and secondary energy
products as
well as renewable and non-renewable energy products. [Do we need here also a definition
of
primary and secondary energy products?] A correlation table between the classification of
energy products and existing internationally accepted classifications, primarily the
Harmonised
Commodity Description and Coding System (HS) and the Central Product Classification
(CPC)
has to be developed to allow for better integration of energy statistics with other areas of
statistics
including international trade statistics. For recommendations on definitions and classification
of
energy products see Chapter 3.
2.7 Production boundary in energy statistics. It is crucial that official energy statistics
establish
a broad understanding of the totality of energy flows and their impacts on society and
environment.
It is recommended, therefore, that the energy production boundary includes production of
energy
products by any economic unit, including households, whether or not the production (i) is
their
principal, secondary or ancillary activity, and (ii) is carried out for sale or delivery to other
economic units or for their own consumption, [Flaring, venting and re-injection are
important
variables especially for air emission. Should these items be considered part of the
production
boundary (thus extending the concept of production); or should they be considered as
losses
in production?].
2.8 Reference territory. For compilation of statistics on energy stocks and flows with a
respect
to the territory of the compiling country it is recommended that the economic territory of a
given
country is used as a general guideline (see BPM6 and SNA2008 for definition). However, in
the
context of energy statistics the following exceptions apply [OG4 is invited to discuss this
issue to
get a general understanding of the issues involved and to provide basis for further
drafting]
C. Energy sector
2.9. Many countries publish various indicators describing activity of their energy sector.
However, the country practices in defining boundary of that sector and the set of main
indicators to
1 From
the “United Nations Framework Classification for Fossil Energy and Mineral Resources” (2004), available online at:
http://www.unece.org/energy/se/pdfs/UNFC/UNFCemr.pdf
IRES, Chapter 2 Scope of energy statistics Draft 1
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describe its activities significantly differ. To improve international comparability of energy
statistics, it is recommended that the energy sector of an economy is defined as comprising
economic units whose principal2 activity is energy extraction, production, manufacturing,
transformation or distribution of energy products. It is further recommended that activities
of
this group are described in terms of activity classifications adopted by the countries for use in
economic statistics providing, where necessary, additional details to meet the user needs.
Countries
should take into account that the UN Statistical Commission recommended for this purpose
International Standard Industrial Classification of All Economic Activities (ISIC). Its latest,
fourth
revision, was adopted by the Commission at its thirty-seventh session (7-10 March 2006).
Examples of units of energy sector are coal mines, oil rigs, refineries, power plants,
geothermal
stations, etc […].
2.10. Statistics on energy sector. To have a better understanding of efforts the society has to
undertake to extract, produce, transform and distribute energy products, it is recommended
that
compilation and dissemination of statistics describing the main characteristics and activities
of
energy sector be considered part of official energy statistics. The recommended statistics
might
include number and size of units, value of their output, intermediate consumption, gross fixed
capital formation, employment etc. See Chapter 6 for details [Please, comment. What does
your
country do in this respect?].
2.11. Energy production outside the energy sector. It should be stressed that energy is
produced
not only by energy sector but also by: enterprises or establishments engaged in energy
production
as a secondary or ancillary activity, that is units not belonging to that sector but which
produce
energy, generally for sale, in addition to their principal activity or in supports to their
principal
activity. The auto-producers include: (i) enterprises which generate some by-products which
are
then either sold (secondary production) or used by the industry as a source of energy
(ancillary
production) and (ii) households that produce energy products (e.g., collect firewood) for own
consumption or for sale on a local market.
[Please, note that the definition of the “energy sector” has fundamental implications in
the
identifications of the statistical units, data items and data collection strategies.
Important
elements of the definitions are: (1) the clear identification whether it includes only
economic
activities engaged in the extraction, transformation and distribution of energy products
as a
principal activity only or as principal, secondary and ancillary activity; and (2) the clear
identification of the type of activities included: extraction, manufacture, production,
transformation and distribution.
(1) the clear identification whether it includes only economic activities engaged in the
extraction, transformation and distribution of energy products as a principal activity
only or
as principal, secondary and ancillary activity
The current text reflect the statistical practice of defining an economic sector in terms
of the
principal economic activity, thus leaving outside the sector secondary and/or ancillary
activities. In this way, however, part of the production of energy products would be
ignored.
Thus it is suggested in the text to define “energy production out side the energy sector”
which
include the part of the production carried out for example, for own use or as a
secondary
2 For
more details on the concept of principal activity, see chapter 6 Sec A
IRES, Chapter 2 Scope of energy statistics Draft 1
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activity. Total production would then include both the production from the energy and
nonenergy
sectors. Similar would be the calculation of the consumption of energy in support of
these activities.
A second option is to include in the energy sector units activities engaged in the
extraction,
transformation and distribution of energy products as principal, secondary or ancillary
activity. In this case, the energy sector would consist of a grouping of units of
homogeneous
production. Units of homogeneous production cannot usually be observed directly; data
collected from the units used in statistical enquiries have to be re-arranged to form
homogeneous branches.
The OG is invited to provide comments on the inclusion/exclusion in the definition of
the
energy sector of secondary and ancillary activities.
(2) the clear identification of the type of activities included: extraction, manufacture,
production, transformation and distribution.
The preliminary text for chapter 5 contains a tentative list of activities generally
included in
the energy sector and mapped into ISIC Rev. 4. The list is based on that provided in the
IEA
Questionnaire.
The OG is invited to provide comments on whether the proposed general definition of
the
energy sector properly reflects the activities in ISIC Rev. 4].
D. Final energy consumption
2.12. Final energy consumption. Final energy consumption refers to any use of energy
products
(for energy and non-energy needs) by final energy consumers. [The definition will be
revised
based on the work of InterEnerStat].
2.13 Classification of final energy consumers. There are different types of final consumers of
energy. They are grouped by countries and various international and regional agencies into
various
sectors. The recommendations on this issue are provided in Chapter 5. It is recommended
that
statistics on final energy consumption by various non-energy sectors as well as selected
statistics
reflecting the main characteristics and activities on various user sectors (such as value added)
[any
views on this?] be considered part of official energy statistics. Such information allows, for
example, for the calculation of indicators for sustainable development3 such as energy
intensity
indicators which link the energy use with the value added, for the end-use energy prices by
fuel
and by sector. For recommendations on user sectors and data items to be compiled see
Chapter 6.
[The chapter might include also the future agreement on terminology and acknowledge
any
deviations from other statistical areas and to highlight the main differences.]
3 IAEA,
UNDESA, IEA, Eurostat, EEA Energy indicators for Sustainable Development: Guidelines and Methodologies (2005) IAEA